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Abstract:

A 2D to 3D image conversion apparatus includes a data queue, a conversion
unit and an offset calculation unit. The data queue receives and
temporarily stores an input data value corresponding to a current pixel.
The conversion unit outputs a current offset table corresponding to a
current depth parameter of the current pixel. The current offset table
includes (m+1) reference offsets corresponding to the current pixel and
neighboring m pixels. The offset calculation unit selects one of the
reference offsets corresponding to the current pixel in the current
offset table and multiple previous offset tables as a data offset
corresponding to the current pixel. The data queue selects and outputs an
output data value corresponding to the current pixel according to an
integer part of the data offset and the input data value.

Claims:

1. A 2D to 3D image conversion apparatus, comprising: a data queue for
receiving and temporarily storing an input data value corresponding to a
current pixel; a conversion unit for outputting a current offset table
corresponding to a current depth parameter of the current pixel, the
current offset table including (m+1) reference offsets corresponding to
the current pixel and neighboring m pixels, m being a positive integer;
and an offset calculation unit for selecting one of the reference offsets
corresponding to the current pixel in the current offset table and
multiple previous offset tables as a data offset corresponding to the
current pixel; wherein the data queue selects and outputs an output data
value corresponding to the current pixel according to an integer part of
the data offset and the input data value.

2. The 2D to 3D image conversion apparatus according to claim 1, wherein
the offset calculation unit selects a maximum value of the reference
offsets as the data offset of the current pixel.

3. The 2D to 3D image conversion apparatus according to claim 1, wherein
the offset calculation unit selects a minimum value of the reference
offsets as the data offset of the current pixel.

4. The 2D to 3D image conversion apparatus according to claim 1, wherein
the m pixels are subsequent to the current pixel.

5. The 2D to 3D image conversion apparatus according to claim 1, wherein
the m pixels are antecedent to the current pixel.

6. The 2D to 3D image conversion apparatus according to claim 1, further
comprising: an interpolation unit for receiving the output data value and
a subsequent data value from the data queue, and performing an
interpolation operation on the output data value and the subsequent data
value according to a fraction part of the data offset to obtain an
interpolation data value.

7. The 2D to 3D image conversion apparatus according to claim 1, wherein
the conversion unit obtains the current offset table from an Offset LUT
according to the current depth parameter.

8. The 2D to 3D image conversion apparatus according to claim 1, wherein
the conversion unit inserts the current depth parameter into a formula to
obtain the current offset table, and the formula is 1, 2, 3, . . . ,
(y-1), y, y, 0, 0, . . . etc. as the current depth parameter is equal to
y.

9. The 2D to 3D image conversion apparatus according to claim 1, wherein
the conversion unit inserts the current depth parameter into a formula to
obtain the current offset table, and the formula is y/(y+1), 2y/(y+1),
3y/(y+1), . . . , (y-1)×y/(y+1), y×y/(y+1), y×y/(y+1),
0, 0, . . . etc. as the current depth parameter is equal to y.

10. The 2D to 3D image conversion apparatus according to claim 1, wherein
m is the maximum possible offset.

11. A 2D to 3D image conversion method, comprising: receiving and
temporarily storing an input data value corresponding to a current pixel;
outputting a current offset table corresponding to a current depth
parameter of the current pixel, the current offset table including (m+1)
reference offsets corresponding to the current pixel and neighboring m
pixels, m being a positive integer; selecting one of the reference
offsets corresponding to the current pixel in the current offset table
and multiple previous offset tables as a data offset corresponding to the
current pixel; and selecting and outputting an output data value
corresponding to the current pixel according to an integer part of the
data offset and the input data value.

12. The 2D to 3D image conversion method according to claim 11, wherein
the step of selecting one of the reference offsets as the data offset of
the current pixel is to select a maximum value of the reference offsets
as the data offset of the current pixel.

13. The 2D to 3D image conversion method according to claim 11, wherein
the step of selecting one of the reference offsets as the data offset of
the current pixel is to select a minimum value of the reference offsets
as the data offset of the current pixel.

14. The 2D to 3D image conversion method according to claim 11, wherein
the m pixels are subsequent to the current pixel.

15. The 2D to 3D image conversion method according to claim 11, wherein
the m pixels are antecedent to the current pixel.

16. The 2D to 3D image conversion method according to claim 11, further
comprising: receiving the output data value and a subsequent data value
from the data queue, and performing an interpolation operation on the
output data value and the subsequent data value according to a fraction
part of the data offset to obtain an interpolation data value.

17. The 2D to 3D image conversion method according to claim 11, further
comprising: obtaining the current offset table from an Offset LUT
according to the current depth parameter.

18. The 2D to 3D image conversion method according to claim 11, further
comprising: inserting the current depth parameter into a formula to
obtain the current offset table; wherein the formula is 1, 2, 3, . . . ,
(y-1), y, y, 0, 0, . . . etc. as the current depth parameter is equal to
y.

19. The 2D to 3D image conversion method according to claim 11, further
comprising: inserting the current depth parameter into a formula to
obtain the current offset table; wherein the formula is y/(y+1),
2y/(y+1), 3y/(y+1), . . . , (y-1)×y/(y+1), y×y/(y+1),
y×y/(y+1), 0, 0, . . . etc. as the current depth parameter is equal
to y.

20. The 2D to 3D image conversion method according to claim 11, wherein m
is the maximum possible offset.

Description:

[0001] This application claims the benefit of Taiwan application Serial
No. 100126234, filed Jul. 25, 2011, the subject matter of which is
incorporated herein by reference.

BACKGROUND

[0002] 1. Technical Field

[0003] The invention relates in general to a 2D to 3D image conversion
apparatus and a method thereof.

[0004] 2. Background

[0005] With vigorous development of modern technology, people start to
seek more real visual enjoyment than a 2D image device provided. Thus
recently related 3D image technology has been matured day by day. To form
3D images, currently general 2D image apparatus have to cooperate 2D
images with corresponding depth tables to rendering dual images
corresponding to 3D glasses to achieve 3D effects by viewing with said 3D
glasses. However, data loss problems often occur in the image warping
procedure of the 2D images cooperated with the corresponding depth
tables.

[0006] Referring to FIG. 1, a schematic illustration of a conventional 2D
to 3D image procedure is shown. In FIG. 1, pixels perform image warping
according to offsets related to depths. For example, an offset
corresponding to a pixel P4 is 3, and an input data value d4 is shifted
as an output data value of a pixel P7. More, an offset corresponding to a
pixel P5 is 1, and an input data value d5 is shifted as an output data
value of a pixel P6. However, as shown in FIG. 1, output data values of
the pixels P1, P5, P8, P9 and P10 are lost. In addition, the input data
values of the pixels P4 and P6 are both shifted as an output data value
of the pixel p7, and the output data values of the pixels P6 and P7
suffers data crossing problems. Hence, not only additional hole filling
but also other image processing have to be performed on the output data
values to obtain desired disparity dual images. Consequently, not only
additional resources have to be exhausted to perform hole filling, but
also the whole efficiency of the image processing system is decreased.

SUMMARY

[0007] The disclosure is directed to a 2D to 3D image conversion apparatus
and a method thereof, utilizing simple depth image based rendering and
capable of converting a 2D image into a 3D image without additional hole
filling.

[0008] According to a first aspect of the present disclosure, a 2D to 3D
image conversion apparatus is provided. The 2D to 3D image conversion
apparatus includes a data queue, a conversion unit and an offset
calculation unit. The data queue is for receiving and temporarily storing
an input data value corresponding to a current pixel. The conversion unit
is for outputting a current offset table corresponding to a current depth
parameter of the current pixel. The current offset table includes (m+1)
reference offsets corresponding to the current pixel and neighboring m
pixels, and m is a positive integer. The offset calculation unit is for
selecting one of the reference offsets corresponding to the current pixel
in the current offset table and multiple previous offset tables as a data
offset corresponding to the current pixel. The data queue selects and
outputs an output data value corresponding to the current pixel according
to an integer part of the data offset and the input data value.

[0009] According to a second aspect of the present disclosure, a 2D to 3D
image conversion method, including the following steps, is provided. An
input data value corresponding to a current pixel is received and
temporarily stored. A current offset table corresponding to a current
depth parameter of the current pixel is outputted. The current offset
table includes (m+1) reference offsets corresponding to the current pixel
and neighboring m pixels, and m is a positive integer. One of the
reference offsets corresponding to the current pixel in the current
offset table and multiple previous offset tables is selected as a data
offset corresponding to the current pixel. An output data value
corresponding to the current pixel is selected and outputted according to
an integer part of the data offset and the input data value.

[0010] The invention will become apparent from the following detailed
description of the preferred but non-limiting embodiments. The following
description is made with reference to the accompanying drawings.

[0012]FIG. 2, a block diagram illustrating a 2D to 3D image conversion
apparatus according to an embodiment is shown.

[0013]FIG. 3 shows a simple schematic illustration of a 2D to 3D image
conversion procedure according to an embodiment.

[0014] FIGS. 4A to 4K show detailed schematic illustrations of a 2D to 3D
image conversion procedure according to an embodiment.

[0015]FIG. 5 shows a block diagram illustrating a 2D to 3D image
conversion apparatus according to another embodiment.

[0016]FIG. 6 shows a flow chart of a 2D to 3D image conversion method
according to an embodiment.

DETAILED DESCRIPTION OF THE INVENTION

[0017] The disclosure proposes a 2D to 3D image conversion apparatus and a
method thereof with simple depth image based rendering, capable of
converting a 2D image into a 3D image without additionally hole filling.

[0018] Referring to FIG. 2, a block diagram illustrating a 2D to 3D image
conversion apparatus according to an embodiment is shown. The 2D to 3D
image conversion apparatus 200 includes a data queue 210, a conversion
unit 220 and an offset calculation unit 230. The data queue 210 receives
and temporarily stores an input data value data_in corresponding to a
current pixel.

[0019] The conversion unit 220 outputs a current offset table
corresponding to a current depth parameter depth_ref of the current
pixel. In implementation, the conversion unit 220 can be designed to
obtain the current offset table from an Offset LUT according to the
current depth parameter depth_ref, or to obtain the current offset table
by inserting the current depth parameter depth_ref into a formula, but it
is not limited thereto and decided according to the design requirements.

[0020] The current offset table includes (m+1) reference offsets
corresponding to the current pixel and neighboring m pixels, and m is a
positive integer and the maximum possible offset. For example, the
current offset table includes 5 reference offsets if the maximum possible
offset is 4. In addition, the neighboring m pixels may be subsequent to
the current pixel, or antecedent to the current pixel, and is not limited
thereto. The offset calculation unit 230 selects one of the reference
offsets corresponding to the current pixel in the current offset table
and multiple previous offset tables as a data offset OFFSET corresponding
to the current pixel. The data offset OFFSET may be a maximum value or a
minimum value of the reference offsets. Then take the data offset OFFSET
be the maximum value as being exemplified, and it is substantially not
limited thereto and can be changed according to the requirements. The
data queue 210 selects and outputs an output data value data_out
corresponding to the current pixel according to an integer part of the
data offset OFFSET and the input data value data_in.

[0022] In addition, the depth parameter depth_ref can be a depth, or other
parameters obtained by image algorithms, such as a shift offset. The
depth is exemplified as an example herein, but it is not limited.
Besides, corresponding to the current depth parameter y, it is assumed
that a formula of the conversion unit 220 for outputting the current
offset table corresponding to the current depth parameter is 1, 2, 3, . .
. , (y-1), y, y, 0, 0, . . . , etc. In FIG. 4A, the data queue 210
receives and temporarily stores an input data value data_in (d1)
corresponding to a current pixel (P1). The conversion unit 220 outputs a
current offset table LUT output (1, 1, 0, 0, 0) corresponding to a
current depth parameter (1) according to the current depth parameter
depth_ref (1) of the current pixel (P1). In the example, the current
offset table LUT output includes (4+1) reference offsets as the maximum
possible depth parameter is set to be 4.

[0023] The offset calculation unit 210 correspondingly compares the
current offset table LUT output with a previous offset table prey (0, 0,
0, 0) for maximization to obtain a new offset table new (1, 1, 0, 0, 0),
which includes the reference offset (1) corresponding to the current
pixel P1 and 4 reference offsets (1, 0, 0, 0) of the subsequent 4 pixels.
The reference offset 1 corresponding to the current pixel P1 is outputted
as the data offset OFFSET (1), and the 4 reference offsets (1, 0, 0, 0)
is regarded as a previous offset table of the next pixel P2. The data
queue 210 selects the first data from right to left based on the input
data value data_in (d1) according to an integer part of the data offset
OFFSET (1) to output an output data value data_out corresponding to the
current pixel P1. Due to the current pixel P1 is the first pixel and
there exists no data at its left side, the output data value data_out
corresponding to the current pixel P1 is (x). In other embodiments, the 4
reference offsets may be 4 neighboring pixels antecedent to the current
pixel P1, or 2 pixels antecedent to the current pixel P1 and 2 pixels
subsequent to the current pixel P1.

[0024] In FIG. 4B, the data queue 210 receives and temporarily stores an
input data value data_in (d2) corresponding to a current pixel (P2). The
conversion unit 220 outputs a current offset table LUT output (1, 1, 0,
0, 0) corresponding to a current depth parameter (1) according to the
current depth parameter depth_ref (1) of the current pixel (P2). The
offset calculation unit 210 correspondingly compares the current offset
table LUT output with the previous offset table prey (1, 0, 0, 0) for
maximization to obtain a new offset table new (1, 1, 0, 0, 0). The
reference offset 1 corresponding to the current pixel P2 is outputted as
the data offset OFFSET (1), and the 4 reference offsets (1, 0, 0, 0) is
regarded as a previous offset table of the next pixel P3. The data queue
210 selects the first data from right to left based on the input data
value data_in (d2) according to an integer part of the data offset OFFSET
(1) to output an output data value data_out (d1) corresponding to the
current pixel P2.

[0025] In FIG. 4C, the data queue 210 receives and temporarily stores an
input data value data_in (d3) corresponding to a current pixel (P3). The
conversion unit 220 outputs a current offset table LUT output (1, 1, 0,
0, 0) corresponding to a current depth parameter (1) according to the
current depth parameter depth_ref (1) of the current pixel (P3). The
offset calculation unit 210 correspondingly compares the current offset
table LUT output with the previous offset table prey (1, 0, 0, 0) for
maximization to obtain a new offset table new (1, 1, 0, 0, 0). The
reference offset 1 corresponding to the current pixel P3 is outputted as
the data offset OFFSET (1), and the 4 reference offsets (1, 0, 0, 0) is
regarded as a previous offset table of the next pixel P4. The data queue
210 selects the first data from right to left based on the input data
value data_in (d3) according to an integer part of the data offset OFFSET
(1) to output an output data value data_out (d2) corresponding to the
current pixel P3.

[0026] In FIG. 4D, the data queue 210 receives and temporarily stores an
input data value data_in (d4) corresponding to a current pixel (P4). The
conversion unit 220 outputs a current offset table LUT output (1, 2, 3,
3, 0) corresponding to a current depth parameter (3) according to the
current depth parameter depth_ref (3) of the current pixel (P4). The
offset calculation unit 210 correspondingly compares the current offset
table LUT output with the previous offset table prey (1, 0, 0, 0) for
maximization to obtain a new offset table new (1, 2, 3, 3, 0). The
reference offset 1 corresponding to the current pixel P4 is outputted as
the data offset OFFSET (1), and the 4 reference offsets (2, 3, 3, 0) is
regarded as a previous offset table of the next pixel P5. The data queue
210 selects the first data from right to left based on the input data
value data_in (d4) according to an integer part of the data offset OFFSET
(1) to output an output data value data_out (d3) corresponding to the
current pixel P4.

[0027] In FIG. 4E, the data queue 210 receives and temporarily stores an
input data value data_in (d5) corresponding to a current pixel (P5). The
conversion unit 220 outputs a current offset table LUT output (1, 1, 0,
0, 0) corresponding to a current depth parameter (1) according to the
current depth parameter depth_ref (1) of the current pixel (P5). The
offset calculation unit 210 correspondingly compares the current offset
table LUT output with the previous offset table prey (2, 3, 3, 0) for
maximization to obtain a new offset table new (2, 3, 3, 0, 0). The
reference offset 2 corresponding to the current pixel P5 is outputted as
the data offset OFFSET (2), and the 4 reference offsets (3, 3, 0, 0) is
regarded as a previous offset table of the next pixel P6. The data queue
210 selects the second data from right to left based on the input data
value data_in (d5) according to an integer part of the data offset OFFSET
(2) to output an output data value data_out (d3) corresponding to the
current pixel P5.

[0028] In FIG. 4F, the data queue 210 receives and temporarily stores an
input data value data_in (d6) corresponding to a current pixel (P6). The
conversion unit 220 outputs a current offset table LUT output (1, 1, 0,
0, 0) corresponding to a current depth parameter (1) according to the
current depth parameter depth_ref (1) of the current pixel (P6). The
offset calculation unit 210 correspondingly compares the current offset
table LUT output with the previous offset table prey (3, 3, 0, 0) for
maximization to obtain a new offset table new (3, 3, 0, 0, 0). The
reference offset 3 corresponding to the current pixel P6 is outputted as
the data offset OFFSET (3), and the 4 reference offsets (3, 0, 0, 0) is
regarded as a previous offset table of the next pixel P7. The data queue
210 selects the third data from right to left based on the input data
value data_in (d6) according to an integer part of the data offset OFFSET
(3) to output an output data value data_out (d3) corresponding to the
current pixel P6.

[0029] In FIG. 4G, the data queue 210 receives and temporarily stores an
input data value data_in (d7) corresponding to a current pixel (P7). The
conversion unit 220 outputs a current offset table LUT output (1, 2, 3,
4, 4) corresponding to a current depth parameter (4) according to the
current depth parameter depth_ref (4) of the current pixel (P7). The
offset calculation unit 210 correspondingly compares the current offset
table LUT output with the previous offset table prey (3, 0, 0, 0) for
maximization to obtain a new offset table new (3, 2, 3, 4, 4). The
reference offset 3 corresponding to the current pixel P7 is outputted as
the data offset OFFSET (3), and the 4 reference offsets (2, 3, 4, 4) is
regarded as a previous offset table of the next pixel P8. The data queue
210 selects the third data from right to left based on the input data
value data_in (d7) according to an integer part of the data offset OFFSET
(3) to output an output data value data_out (d4) corresponding to the
current pixel P7.

[0030] In FIG. 4H, the data queue 210 receives and temporarily stores an
input data value data_in (d8) corresponding to a current pixel (P8). The
conversion unit 220 outputs a current offset table LUT output (1, 2, 3,
4, 4) corresponding to a current depth parameter (4) according to the
current depth parameter depth_ref (4) of the current pixel (P8). The
offset calculation unit 210 correspondingly compares the current offset
table LUT output with the previous offset table prey (2, 3, 4, 4) for
maximization to obtain a new offset table new (2, 3, 4, 4, 4). The
reference offset 2 corresponding to the current pixel P8 is outputted as
the data offset OFFSET (2), and the 4 reference offsets (3, 4, 4, 4) is
regarded as a previous offset table of the next pixel P9. The data queue
210 selects the second data from right to left based on the input data
value data_in (d8) according to an integer part of the data offset OFFSET
(2) to output an output data value data_out (d6) corresponding to the
current pixel P8.

[0031] In FIG. 4I, the data queue 210 receives and temporarily stores an
input data value data_in (d9) corresponding to a current pixel (P9). The
conversion unit 220 outputs a current offset table LUT output (1, 2, 3,
4, 4) corresponding to a current depth parameter (4) according to the
current depth parameter depth_ref (4) of the current pixel (P9). The
offset calculation unit 210 correspondingly compares the current offset
table LUT output with the previous offset table prey (3, 4, 4, 4) for
maximization to obtain a new offset table new (3, 4, 4, 4, 4). The
reference offset 3 corresponding to the current pixel P9 is outputted as
the data offset OFFSET (3), and the 4 reference offsets (4, 4, 4, 4) is
regarded as a previous offset table of the next pixel P10. The data queue
210 selects the third data from right to left based on the input data
value data_in (d9) according to an integer part of the data offset OFFSET
(3) to output an output data value data_out (d6) corresponding to the
current pixel P9.

[0032] In FIG. 4J, the data queue 210 receives and temporarily stores an
input data value data_in (d10) corresponding to a current pixel (P10).
The conversion unit 220 outputs a current offset table LUT output (1, 2,
3, 4, 4) corresponding to a current depth parameter (4) according to the
current depth parameter depth_ref (4) of the current pixel (P10). The
offset calculation unit 210 correspondingly compares the current offset
table LUT output with the previous offset table prey (4, 4, 4, 4) for
maximization to obtain a new offset table new (4, 4, 4, 4, 4). The
reference offset 4 corresponding to the current pixel P10 is outputted as
the data offset OFFSET (4), and the 4 reference offsets (4, 4, 4, 4) is
regarded as a previous offset table of the next pixel P11.

[0033] The data queue 210 selects the fourth data from right to left based
on the input data value data_in (d10) according to an integer part of the
data offset OFFSET (4) to output an output data value data_out (d6)
corresponding to the current pixel P10.

[0034] In FIG. 4K, the data queue 210 receives and temporarily stores an
input data value data_in (d11) corresponding to a current pixel (P11).
The conversion unit 220 outputs a current offset table LUT output (1, 2,
3, 4, 4) corresponding to a current depth parameter (4) according to the
current depth parameter depth_ref (4) of the current pixel (P11). The
offset calculation unit 210 correspondingly compares the current offset
table LUT output with the previous offset table prey (4, 4, 4, 4) for
maximization to obtain a new offset table new (4, 4, 4, 4, 4). The
reference offset 4 corresponding to the current pixel P11 is outputted as
the data offset OFFSET (4), and the 4 reference offsets (4, 4, 4, 4) is
regarded as a previous offset table of the next pixel P12. The data queue
210 selects the fourth data from right to left based on the input data
value data_in (d11) according to an integer part of the data offset
OFFSET (4) to output an output data value data_out (d7) corresponding to
the current pixel P11.

[0035] Referring concurrently to FIG. 3 and FIGS. 4A to 4K, it can be
obtained that the 2D to 3D image conversion apparatus of the embodiment
does not cause data loss problems, thereby needing no additional
follow-up hole filling processing to correct the images. Meanwhile, it
can be observed in FIG. 3 and FIGS. 4A to 4K that there exists no data
crossing problems. In addition, the conversion unit 220 may also output
the current offset table according to other formulas, such as y/(y+1),
2y/(y+1), 3y/(y+1), . . . , (y-1)×y/(y+1), y×y/(y+1),
y×y/(y+1), 0, 0, . . . etc. as the current depth parameter is equal
to y.

[0036] Besides, the data offset can be accurate to the digit to make the
3D image smoother. Referring to FIG. 5, a block diagram illustrating a 2D
to 3D image conversion apparatus according to another embodiment is
shown. Similar to the 2D to 3D image conversion apparatus 200, the 2D to
3D image conversion apparatus 500 includes a data queue 510, a conversion
unit 420 and an offset calculation unit 530; in addition, the 2D to 3D
image conversion apparatus 500 further includes an interpolation unit
540. The interpolation unit 540 receives the output data value data_out
and a subsequent data value data_outnex from the data queue 510, and
performs an interpolation operation on the output data value data_out and
the subsequent data value data_outnex according to a fraction part
offset_frac of the data offset to obtain an interpolation data value
data_out'. In FIG. 5, the interpolation operation may be 2 points linear
interpolation or S-curve interpolation, and it is not limited thereto.

[0037] The disclosure further proposes a 2D to 3D image conversion method,
referring to a flow chart of a 2D to 3D image conversion shown in FIG. 6.
After the start, in step S600, an input data value corresponding to a
current pixel is received and temporarily stored. Next, in step S610, a
current offset table corresponding to a current depth parameter of the
current pixel is outputted. The current offset table includes (m+1)
reference offsets corresponding to the current pixel and neighboring m
pixels, and m is a positive integer. Then, in step S620, one of the
reference offsets corresponding to the current pixel in the current
offset table and multiple previous offset tables is selected as a data
offset corresponding to the current pixel. In step S630, an output data
value corresponding to the current pixel is selected and outputted
according to an integer part of the data offset and the input data value,
thus the 2D to 3D image conversion is completed and finished.

[0038] The detailed principles of the above 2D to 3D image conversion
method have been described in FIGS. 2 to 4K and related content, and
related operations, such as how to generate the current offset table, and
how to select m, etc. can also be obtained from the above embodiments, so
detailed description thereof will be omitted.

[0039] The 2D to 3D image conversion apparatus and method proposed in the
embodiments of the disclosure utilizes simple depth image based
rendering, and does not cause output data loss problems, thereby capable
of converting a 2D image into a 3D image without additional hole filling.
In addition, it can avoid generating data crossing problems by suitable
conversion design.

[0040] While the invention has been described by way of example and in
terms of a preferred embodiment, it is to be understood that the
invention is not limited thereto. On the contrary, it is intended to
cover various modifications and similar arrangements and procedures, and
the scope of the appended claims therefore should be accorded the
broadest interpretation so as to encompass all such modifications and
similar arrangements and procedures.